Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to gain some insight into the relationship of human papillomavirus (HPV) infection to p53 expression and to some pathological parameters in precancerous lesions of the larynx. Formalin-fixed paraffin-embedded tissue sections containing human laryngeal precancerous lesions were screened for p53 protein by immunohistochemistry with the monoclonal antibody DO7 and for the presence of HPV infection by polymerase chain reaction with consensus primers directed against the E6 gene. The presence of p53 protein was detected in 31 of 57 specimens (54.4%) including 7 of 9 cases with mild dysplasia (78%), in 4 of 9 cases with moderate dysplasia (44%), and in 15 of 23 cases with severe dysplasia (65%). Of 16 samples with keratotic benign squamous metaplasia, 5 were also p53 positive (31%). Of 6 samples that were HPV positive, all were of type 16. Interestingly, 3 of the 6 HPV-positive samples were p53 negative. There was 1 HPV-positive case with strong p53 staining and 2 HPV-positive cases with minimal p53 staining. The 2 HPV-positive cases with minimal p53 staining had mild dysplasia. The HPV-positive case with strong p53 staining displayed severe dysplasia. Of 23 cases that were both HPV and p53 negative, 11 presented with keratosis and no dysplasia, 5 with moderate dysplasia, and 7 with severe dysplasia. Our data indicate that nuclear accumulation of p53 protein, presumably resulting from p53 gene mutation, may occur in HPV-infected epithelial tissues. On the other hand, there are many precancer lesions, some exhibiting moderate or severe dysplasia, that are both HPV negative and p53 unreactive, suggesting that alterations of genes other than the E6 oncogene and the p53 tumor suppressor gene play a role in early laryngeal carcinogenesis.
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PMID:Expression of p53 protein related to the presence of human papillomavirus infection in precancer lesions of the larynx. 788 42

To study the mechanism and risk of human skin cancer from solar light, we exposed human skin transplanted to severe combined immunodeficient mice to daily doses of UVB for periods of approximately 2 years. We have succeeded for the first time in inducing cancer and solar (actinic) keratosis in human skin by UVB. Of 18 normal skins exposed to doses of 7.3 x 10(5) to 1.8 x 10(6) J/m2, 14 actinic keratoses (77.8%) and 3 squamous cell carcinomas (16.7%) developed, whereas neither actinic keratosis nor cancer was observed in 15 human skins not exposed to UVB. Each human skin showed a different susceptibility, and skins sensitive for actinic keratosis were also sensitive for cancer induction. Among p53 mutations at various sites, mutation at codon 242 (C TGC --> C CGC; Cys --> Arg) was specifically observed in both skin cancers and actinic keratoses. Furthermore, double or triple mutations were induced in all UVB-induced skin cancers and in three of eight actinic keratoses. Most of the mutations (17 of 20) occurred at dipyrimidine sites.
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PMID:Induction of cancer, actinic keratosis, and specific p53 mutations by UVB light in human skin maintained in severe combined immunodeficient mice. 918 98

In our 5-year biopsy study (1991 95) 51% of keratoses and 16% of adult-onset papillomas contained certain degrees of dysplasia. Koilocytosis associated with HPV infection was prominent in papillomas and the majority of keratosis but negligible in cancer. Using mouse monoclonal antibody against human p53 we detected by immunohistochemistry mutated p53 overexpression not only in cancer but in some cases of keratoses and papillomas. CD44 is a multifunctional integral cell membrane glycoprotein and is found in many mesenchymal, epithelial and tumor cells. CD44 has a great number of splice variants, isoforms supposedly implicated in development, progression and metastasis formation of tumors. Using monoclonal antibody to CD44 our study suggests that the expression of pan CD44 at successive stages of human laryngeal carcinogenesis gives preliminary information about the selection advantage to the tumor cells.
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PMID:New aspects in the pathology of the preneoplastic lesions of the larynx. 919 82

Expression of apoptosis-associated proteins was evaluated in premalignant and malignant oral epithelial lesions, to test the hypothesis that protein regulation of apoptosis may be altered in the development of oral squamous cell carcinoma. Ninety archived paraffin-embedded specimens from 25 patients (two or more sequential biopsies each) and eight control specimens were evaluated in immunohistochemically stained sections for tumor suppressor protein p53, p53 binding protein mdm-2, and apoptosis regulatory proteins Bcl-2, Bcl-X, Bax, and Bak. The initial histologic diagnosis for 17/25 patients was either focal keratosis, mild dysplasia, or moderate dysplasia; the initial diagnosis for the remaining eight patients ranged from severe dysplasia to moderately differentiated squamous cell carcinoma. Thirty of 90 specimens showed positive p53 expression, nine of which were dysplasias. In patients with one or more lesions displaying p53 expression, there was increased intensity of staining with disease progression. Bak was expressed in 57/90 specimens, including 27 dysplasias of various grades. There was also a significantly increased intensity of Bak staining with disease progression, which did not appear to be dependent upon p53 status. Bcl-X was expressed in 73/90 specimens, with staining displayed earlier in premalignant lesions than either p53 or Bak. Ten of 90 specimens were positive for Bcl-2 (all were dysplasias or carcinomas), and only 2/90 specimens were positive for Bax. Eleven of 90 specimens were positive for mdm-2; six of which were also positive for p53. These data show that apoptosis-associated proteins are altered in variable patterns in both premalignant and malignant oral epithelial lesions. p53 and especially Bak and Bcl-X are expressed early; Bax is largely absent; and Bcl-2 and mdm-2 show sporadic expression in the development of oral premalignant and malignant disease.
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PMID:Apoptosis-associated proteins and the development of oral squamous cell carcinoma. 1021 14

In order to study the altered Rb, bcl-2 and p53 proteins expression during laryngeal carcinogenesis and to elucidate the role of these molecules in the development and progression of the lesions, we have examined the immunohistochemical expression of these markers in a series of 41 squamous cell carcinomas, 14 cases of in situ carcinoma, 47 with epithelial dysplasia, 11 papillomas and 20 cases of keratosis. Rb protein was expressed in 69.7% (> 5% positive neoplastic cells) of squamous cell carcinomas and p53 in 40% (> 5% positive cells). There was a strong statistically significant difference for Rb, Ki-67 and PCNA immunostaining between malignant, premalignant and benign lesions, increasing from keratosis, papillomas, dysplasia to carcinoma in situ or infiltrating squamous Ca. Rb protein expression was also strongly correlated with p53, Ki-67 and PCNA, while p53 protein was strongly correlated with Ki-67 (p = 0023) and PCNA (p = 0.0031) indices, in all lesions. In conclusion Rb and p53 altered proteins expression seems to play an active role in laryngeal carcinogenesis, probably from the early phase, and is correlated with proliferative activity. Also, Rb protein expression is correlated with the progression of the lesion and could be considered as indication of poor prognosis in laryngeal lesions.
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PMID:Altered patterns of retinoblastoma gene product expression in benign, premalignant and malignant epithelium of the larynx: an immunohistochemical study including correlation with p53, bcl-2 and proliferating indices. 1022 95

CD44 is an integral membrane glycoprotein that has diverse functions in cell-cell and cell-substrate interactions. It has been suggested that it may be a determinant of metastatic and invasive behavior in carcinomas. The immunohistochemical expression of CD44 was examined in a series of 34 squamous cell carcinomas, 13 in situ carcinomas, 35 cases with various degrees of epithelial dysplasia, 10 papillomas and 17 cases of keratosis. We used the monoclonal mouse anti-human phagocytic glycoprotein-1 CD44 (clone DF 1485), on formalin-fixed, paraffin-embedded tissue. CD44 expression was correlated with the expression of Rb and p53 proteins, with the proliferative indices Ki-67 and PCNA as well as with conventional clinicopathological data. The mean value of CD44 expression was 78.84 in squamous cell carcinomas, 78.04 in situ carcinomas, 54.93 in dysplasia, 26.8 in papillomas and 24.97 in keratosis. There was no significant difference of CD44 expression between in situ and invasive carcinomas. However, a strong difference of reaction between carcinomas and the other cases was observed. CD44 expression was statistically higher in dysplastic lesions than the cases of keratosis (p < 0.0001) and papillomas (p = 0.01). In the group of invasive carcinomas, CD44 expression was statistically correlated with pRb (p = 0.011), while in preinvasive lesions it was correlated with PCNA (p = 0.016). The relationship with the degree of dysplasia or grade of carcinoma and p53 protein expression was insignificant. These observations suggest that CD44 expression may be involved in the multiple mechanism of the development and progression of laryngeal lesions and may help to predict the risk of transformation of the benign or precancerous lesions to cancer.
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PMID:Glycoprotein CD44 expression in benign, premalignant and malignant epithelial lesions of the larynx: an immunohistochemical study including correlation with Rb, p53, Ki-67 and PCNA. 1050 27

Expression of cell cycle regulatory proteins was evaluated in premalignant and malignant oral epithelial lesions, to test the hypothesis that protein regulation of the cell cycle may be altered in the development of oral squamous cell carcinoma. Archived paraffin-embedded specimens (n = 90) from 25 patients with recurrent or persistent lesions were evaluated in immunohistochemically stained sections for cell cycle regulatory proteins p53, Rb, Cyclin D1, p27, and p21. The cell cycle was also evaluated by expression of nuclear protein Ki 67. Sections were graded semiquantitatively using a 0-3 + scale to indicate the percentage of positively stained cells. The initial histologic diagnosis for 17/25 patients was either focal keratosis, mild dysplasia, or moderate dysplasia; the initial diagnosis for the remaining eight patients ranged from severe dysplasia to moderately differentiated squamous cell carcinoma. Thirty-three of 90 specimens showed positive p53 expression, 11 of which were dysplasias. Eighty-nine of 90 specimens, from all stages of disease, showed positive Rb expression. Twenty-three of 90 specimens showed positive Cyclin D1 expression, typically in the later stages (carcinoma) of a patient's disease. Eighty-four of 90 specimens showed positive p21 expression; while 55 of 90 specimens were positive for p27. In control mucosa, p27 was highly expressed, while Rb and p21 proteins were expressed at relatively low levels; p53 and Cyclin D1 proteins were largely absent. Generally, staining of p53, Rb, p21, and Ki 67 increased with time in serial biopsies, while p27 showed decreased staining with disease progression. These data show that cell cycle regulatory proteins are altered in both premalignant and malignant disease, and that protein phenotypes are heterogeneous. P53 expression is seen early, and Cyclin D1 expression is seen late in the development of oral premalignant and malignant disease. Expression of p53, Rb, p21 and Ki67 increased, while p27 decreased, with disease progression.
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PMID:Cell cycle proteins and the development of oral squamous cell carcinoma. 1062 56

In this study we evaluated the immunohistochemical expression of metallothionein (MT) in 44 squamous cell carcinomas, 14 cases of in situ carcinoma, 47 with epithelial dysplasia, 11 papillomas and 21 cases of keratosis. The MT expression was studied in correlation with p53 protein expression and the proliferative cell nuclear antigen (PCNA). The monoclonal antibodies E9 (anti-MT), DO-7 (which reacts with a denaturation-resistant epitope in wild-type and mutant p53) and PC10 (anti-PCNA) on formalin-fixed, paraffin-embedded tissue were used employing the immunoperoxidase (ABC) method. The immunohistochemical localization of MT has shown its rather ubiquitous presence in the cytoplasm and nucleus of both benign and malignant epithelial cells. In most cases the adjacent "normal" epithelium showed low positivity in the basal portion. The mean value of metallothionein expression was 35.73 in squamous cell carcinomas, 32.21 in in situ carcinomas, 11.86 in dysplastic epithelium, 5.10 in papillomas and 3.5 in keratosis. In carcinomas, low MT expression (< 10% of neoplastic cells) was observed in 20.5% of the cases, moderate (10%-50% of neoplastic cells) in 54.5% and extensive expression (> 50% of neoplastic cells) in 25% of the cases. We did not find any statistically significant difference of MT expression between in situ and infiltrating carcinomas, while we did observe a significant difference between carcinomas and the other groups. There was a statistically significant difference in the PCNA values in both benign and malignant lesions, while no statistically significant difference was observed in p53 protein expression in the above groups. A positive correlation between MT expression and the PCNA value (p < 0.0001) in the benign and malignant groups was detected. The PCNA value was also correlated with the p53 protein expression (p = 0.001). No correlation was found between MT and p53 protein expression. In conclusion, these results suggest that the MT expression may play a role in the development of malignant disease of the larynx, from the early phase of laryngeal carcinogenesis, independently from the p53 expression. It is also possible to contribute to tumour cell growth, as determined by the PCNA score.
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PMID:Immunohistochemical expression of metallothionein in benign premalignant and malignant epithelium of the larynx: correlation with p53 and proliferative cell nuclear antigen. 1063 15

Clinical studies in several tumour types have shown a strong correlation between cathepsin D expression and tumour progression. Immunohistochemical staining for cathepsin D (clone D13A) was performed in paraffin embedded-tissues from 39 invasive squamous cell carcinomas, 13 in situ carcinomas, 35 cases of dysplasia, 10 papillomas and 17 cases of keratosis. The association between cathepsin D expression and CD44, p53, Rb proteins and proliferation indices (Ki-67, PCNA) was assessed by univariate analysis. Cathepsin D was highly positive in the groups of carcinomas compared to other lesions (p < 0.0001). A statistically significant correlation of cathepsin D expression with CD44 expression was observed in invasive cancers (p = 0.037). The relationship of cathepsin D immunoreactivity with p53, Rb and proliferation indices was insignificant. The results show that cathepsin D is expressed in a higher proportion of cancerous lesions of the larynx than in non cancerous or premalignant lesions, a fact which suggests that cathepsin D may be involved in laryngeal tumour cell growth process.
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PMID:Immunohistochemical expression of cathepsin D in laryngeal epithelial lesions: correlation with CD44 expression, p53 and Rb status and proliferation associated indices. 1065 92

Mutations in the p53 gene--which codifies anuclear phosphoprotein that acts as a tumor suppressor gene--is the most common genetic alteration in head and neck cancers. The aim of the present study was to investigate the prognostic significance of p53 protein over expression in squamous cell laryngeal carcinoma. To do so we analyzed 31 patients affected by precancerous lesions of the larynx who had undergone multiple biopsy between 1980 and 1995. Twenty-five of these patients later developed laryngeal carcinoma. In this group of patients, 51 biopsies were performed for precancerous lesions (17 hyperplasia, 3 light dysplasia, 23 moderate dysplasia, 8 severe dysplasia) prior to evidence of laryngeal cancer (2.04 biopsies/patient). In the group of patients who did not develop laryngeal cancer, 18 biopsy were performed (2.2 biopsies/patient) and histology revealed: 5 keratosis, 5 light dysplasia, 4 moderate dysplasia and 4 grave dysplasia. Using the immunohistopathological staining technique, 69 formalin-fixed, paraffin-embedded precancerous samples and 25 laryngeal carcinomas were examined for p53 over expression. The monoclonal antibody Pab 1801 was used with the avidinbiotin immunoperoxidase technique; p53 intensity of expression was assessed and correlated with clinical-pathological parameters. Over expression of the p53 protein was found in 56.8% of the precancerous lesions (41% of the hyperplastic lesions, 66% of light dysplastic lesions, 60% of moderate dysplastic lesions and 75% of severe dysplastic lesions) in the group patients who did develop laryngeal cancer and in 22.2% of the precancerous lesions in the group of patients that did not. The transformed lesions showed a strong correlation between intensity of positivity and grade of cellular atypia. Further in 93.3% of the patients with p53 positive precancerous lesions which later developed into laryngeal cancer, p53 over expression was present in the cancerous lesions. There was no significant correlation between p53 immuno reactivity and such clinico pathological tumor parameters as TNM staging and tumorrecurrence. On the other hand, there was a correlation between p53 overexpression and differentiation grading: p53 overexpression was found in 75% of the poorly differentiated tumors, 58.3% of moderately differentiated and 44.4% of well differentiated tumors. The fact that p53 is detected in preneoplastic lesions suggests that p53 gene alteration takes place very early in laryngeal carcinoma and moderate-to-high p53 expression constitutes a high risk of transformation into cancer; on the other hand low expression may reflect reversible changes that can be attributed to the genotoxic effects of tobacco smoking. In conclusion the present data suggest that p53 over expression could be a good prognostic marker in predicting which precancerous laryngeal lesions will progress into cancer.
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PMID:[The role of p53 tumor suppressor gene as prognostic factor in laryngeal squamous cell carcinoma]. 1087 57


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